Kafeini

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Kafeini (kutoka Kiingereza caffeine) ni dutu ya alkaloidi katika mimea mbalimbali hasa mbuni na mchai. Inaathiri neva za mwanadamu ikiondoa uchovu na kuamsha ubongo.

Matumizi yake ni hasa katika vinywaji vya kahawa, chai na kinywaji cha mate ya Amerika Kusini, lakini pia katika madawa ya tiba na vinywaji nishati (energy drinks).

Kafeini kikemia[hariri | hariri chanzo]

Kafeini katika hali safi ni unga wa fuwele nyeupe wenye ladha chungu. Fomula yake ya kikemia ni C8H10N4O2. Inajengwa ndani ya mimea kama kinga dhidi ya wadudu maana kwao ni kama sumu.

Kafeini na afya[hariri | hariri chanzo]

Wanadamu wanatumia sana kafeini kwa kusudi la kuondoa uchovu, lakini inaweza pia kusababisha matatizo ya afya. Inaongeza shinikizo la damu na kasi ya pigo la moyo.

Huduma ya afya nchini Kanada inapendekeza matumizi yasizidi miligramu 2.5 kwa kila kilogramu ya uzito wa mwili. Watu waliozoea wanaweza kustahimili zaidi, lakini kiasi chote kisizidi miligramu 400.[1]

Taasisi ya afya ya Waverly nchini Marekani inaona vikombe vikubwa 3 vya robo lita kuwa matumizi ya wastani ya kahawa kwa mtu mzima kwa siku moja. Hii inalingana na miligramu 250 za kafeini. Kunywa vikombe 10 vya ukubwa huo kunatazamwa kuwa nyingi mno.

Watu wanaoitumia mno wanaweza kupata uraibu yaani mwili uananza kutegemea kafeini na kukosa raha kama haupati dawa hii tena.

Watu wenye matatizo ya usingizi au moyo dhaifu wanashauriwa kuepukana na kafeini. Kuzidi kwa kafeini mwilini kunaweza kusababisha hali inayofanana kiasi na ulevi. Kutokana na athira hii kunywa kahawa kuliwahi kukataliwa na wataalamu kadhaa wa Uislamu (lakini leo hii inakubaliwa kama inanyewa kwa kiasi) na inatazamwa kuwa marufuku kati ya wafuasi wengi wa Wasabato[2] na Wamormoni.

Zamani ni watu waliokunywa kahawa nyingi mno walioweza kupata matatizo ya kiafya kutokana na kafeini. Tangu kupatikana kwa vinywaji nishati kama Red Bull hatari imeongezeka hasa upande wa vijana kwa sababu vinywaji hivi vina kiasi cha kafeini sawa na kahawa kali.

Kinyume chake kuna dalili ya kwamba matumizi ya wastani ina faida kwa afya[3].

Viwango vya kafeini katika vinywaji na vyakula[hariri | hariri chanzo]

Kiwango cha kafeini katika vyakula na vinywaji[4][5][6][7][8]
Bidhaa Kiasi Kafeini kwa kila kiasi (mg) Kafeini (mg/L)
Kidonge cha kafeini (kawaida) kidonge 1 &0000000000000100.000000100
Kidonge cha kafeini (nguvu ya ziada) kidonge 1 &0000000000000200.000000200
Kidonge cha Excedrin kidonge 1 &0000000000000065.00000065
chokoleti cha Hershey's Special Dark (45% kakao) &0000000000000031.00000031
chokoleti cha Hershey's Milk Chocolate (11% kakao) &0000000000000010.00000010
Kahawa ya filta &0000000000000115.000000115–175 &0000000000000555.000000555–845
Kahawa ya filta, kafeini ikipunguzwa &0000000000000005.0000005–15 &0000000000000024.00000024–72
Kahawa ya espresso &0000000000000100.000000100 &0000000000001691.0000001,691–2,254
Chai – nyeusi, kijani , – dakika 3 katika maji &0000000000000022.00000022–74[7][8] &0000000000000124.000000124–418
Guayakí yerba mate (majani) &0000000000000085.00000085[9] &0000000000000358.000000358
Coca-Cola Classic &0000000000000034.00000034 &0000000000000096.00000096
Pepsi Max &0000000000000069.00000069 &0000000000000194.000000194
Red Bull &0000000000000080.00000080 &0000000000000320.000000320

Bidhaa zenye kafeini ni kahawa, chai, vinywaji vya soda ("cola"), vinywaji nishati, chokoleti,[10] vidonge vya kafeini.

Marejeo[hariri | hariri chanzo]

Kigezo:Tanbihi

  1. Zaasisi ya Health Canada kuhusu kafeini
  2. Mwongozo wa Kesha la Asubuhi, (uk. 314) na Ellen G. White, mwanzilishaji wa Usabato
  3. Drinking Coffee: More Good Than Harm?, by Written by Catharine Paddock PhD Published: Monday 9 July 2012 , Medical News today
  4. Caffeine Content of Food and Drugs. Nutrition Action Health Newsletter. Center for Science in the Public Interest (1996). Jalada kutoka ya awali juu ya 14 June 2007. Iliwekwa mnamo 3 August 2009.
  5. Caffeine Content of Beverages, Foods, & Medications. The Vaults of Erowid (7 July 2006). Iliwekwa mnamo 3 August 2009.
  6. Caffeine Content of Drinks. Caffeine Informer. Iliwekwa mnamo 8 December 2013.
  7. 7.0 7.1 Chin JM, Merves ML, Goldberger BA, Sampson-Cone A, Cone EJ (October 2008). "Caffeine content of brewed teas". J Anal Toxicol 32 (8): 702–4. doi:10.1093/jat/32.8.702 . PMID 19007524 .
  8. 8.0 8.1 Richardson, Bruce (2009). Too Easy to be True. De-bunking the At-Home Decaffeination Myth. Elmwood Inn. Iliwekwa mnamo 12 January 2012.
  9. Traditional Yerba Mate in Biodegradable Bag. Guayaki Yerba Mate. Iliwekwa mnamo 17 July 2010.
  10. Matissek R (1997). "Evaluation of xanthine derivatives in chocolate: nutritional and chemical aspects". European Food Research and Technology 205 (3): 175–84. doi:10.1007/s002170050148 . Kigezo:INIST.